Central Kappa-Opioid Receptor Antagonism and Metabolic Outcomes

To assess the chronic central effects of the k-OR selective antagonist, PF-04455242, WT, and Oprk1−/−animals were subjected to OVX 21 days after the surgery PF-04455242 (3.4 nmol/day) or vehicle (VH) were delivered i.c.v. via brain infusion kit 3 (1–3 mm) for 7 days through a catheter tube connecting the i.c.v. cannula to an osmotic minipump (model 1007D, Alzet Osmotic Pumps; DURECT, Cupertino, CA, USA), as previously described [43 (link),46 (link),50 (link)]. The mini pump was inserted in a subcutaneous pocket on the dorsal surface. The incision was closed with sutures, and mice were kept warm until full recovery. Body weight, food intake, lipid metabolism, and thermogenesis/browning were analyzed.